Issued wake turbulence warning while on long final for departing a/c

WannFly

WannFly

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last evening, i was on a long straight in for rny 36, got a caution wake turbulence while i was 8 miles out for a departing big iron from rny 36. got me a little off-guard as to why do i care about his wake since i wasnt going through his flightpath, unless i am going around. got one more about 3 mile final as another big iron fedex took off.

I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) one or even in the air if i am climbing and they are descending but this is the first time i have been issued that warning not once but twice while i am landing and they are taking off.

if it matters winds were 040 @5 on the surface, about 060@15 where i was on the glide path and rny 36 was being used.

thoughts?
 
unsafervguy said:
because the controllers book says they will issue it, or the controller just wanted to give you heads up. I never complain when a controller tries to help me out by doing more than they have to.
Click to expand...

Not complaining, just wondering
 
I got such a warning once, noted the point at which the departing jet rotated, and made sure I was down before that.
 
As a student I was doing touch and goes at Kenai Airport while an oil company charter 737 was doing the same. That was interesting.
 
WannFly said:
last evening, i was on a long straight in for rny 36, got a caution wake turbulence while i was 8 miles out for a departing big iron from rny 36. got me a little off-guard as to why do i care about his wake since i wasnt going through his flightpath, unless i am going around. got one more about 3 mile final as another big iron fedex took off.

I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) one or even in the air if i am climbing and they are descending but this is the first time i have been issued that warning not once but twice while i am landing and they are taking off.

if it matters winds were 040 @5 on the surface, about 060@15 where i was on the glide path and rny 36 was being used.

thoughts?
Click to expand...

WAKE TURBULENCE APPLICATION
b. Issue wake turbulence advisories, and the position, altitude if known, and the direction of flight of:
1. The super or heavy to aircraft landing behind a departing/arriving super or heavy on the same or parallel runways separated by less than 2,500 feet.
2. The B757/large aircraft to a small aircraft landing behind a departing/arriving B757/large aircraft on the same or parallel runways separated by less than 2,500 feet.
REFERENCE−
AC 90−23, Aircraft Wake Turbulence, Para 12, Pilot Responsibility.
FAA Order JO 7110.65, Para 3−10−10, Altitude Restricted Low Approach.
EXAMPLE−
1. “Runway two seven left cleared to land, caution wake turbulence, heavy Boeing 747 departing runway two seven right.”
2. “Number two follow Boeing 757 on 2-mile final. Caution wake turbulence.”
3. “Traffic, Boeing 737 on 2−mile final to the parallel runway, runway two six right, cleared to land. Caution wake turbulence.”
 
They have specific criteria for issuing wake turbulence advisories as indicated in previous post but can issue it just by controller judgment as well (B).

DF73B3E2-8773-4EF9-8052-AE3FF187E0BC.jpeg
 
GeorgeC said:
I got such a warning once, noted the point at which the departing jet rotated, and made sure I was down before that.
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Yeah, I've always made it a habit to have as much runway ahead of me as is practical when landing, so the takeoff vortices won't be an issue.
 
WannFly said:
I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) ....?
Click to expand...

Won't work here ... they use every bit of runway due to high DA. I lift off by the 1000 foot markers and avoid their takeoff path after their rotation point ...
 
WannFly said:
last evening, i was on a long straight in for rny 36, got a caution wake turbulence while i was 8 miles out for a departing big iron from rny 36. got me a little off-guard as to why do i care about his wake since i wasnt going through his flightpath, unless i am going around. got one more about 3 mile final as another big iron fedex took off.

I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) one or even in the air if i am climbing and they are descending but this is the first time i have been issued that warning not once but twice while i am landing and they are taking off.

if it matters winds were 040 @5 on the surface, about 060@15 where i was on the glide path and rny 36 was being used.

thoughts?
Click to expand...
Please note the emphasized text. I thought you wanted to be in the air before their rotation, for the reason noted below

jordane93 said:
Because wake is generated at the point of rotation. You should plan to touchdown before that airplane rotates which probably wasn’t an issue for you.
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I also thought the vortices tended to descend, another reason to be in the air prior to the large plane's rotation?
 
Cap'n Jack said:
I also thought the vortices tended to descend, another reason to be in the air prior to the large plane's rotation?
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The OP was on final in the air when the other aircraft was departing unless I misread the post. In that case, the airplane on the ground isn’t generating any wake until they rotate.
 
jordane93 said:
The OP was on final in the air when the other aircraft was departing unless I misread the post. In that case, the airplane on the ground isn’t generating any wake until they rotate.
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I was responding to this part of the initial post:
WannFly said:
I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) one
Click to expand...
Italics mine for emphasis.
 
I’ve been flipped 90 degrees when vectored under a 767 turning final. Semi expected but still eye opening none the less. What i didn’t even consider before it happened, was helo wake turbulence. Was holding in position to let a Blackhawk approach across the runway in front of me. It landed, and i was cleared. I blasted through the rotor wash just out of ground effect and got tossed about pretty good. Not something I would have liked at such low altitude. The tower didn’t bother offering a caution. Any wake turb announcement from ATC is just fine with me.
 
you want to see wake turbulence? when I was based at F54, now KGKY, they were developing the V-22 there. come in behind that thing and you will feel wake turbulence.
 
Cap'n Jack said:
Please note the emphasized text. I thought you wanted to be in the air before their rotation, for the reason noted below
Click to expand...

i cant out climb a heavy, or anything else other than may be a cub lol, typically i would always wait 3 mins at least. in rare occasions if i am taking off from crossing runway, say the heavy took off from 36 and i am taking off from 27, i will roll past where the crossing point of the runway is and then take off. of course all of these depends on winds. if its gusting to 20 (common occurrence here) that wake would dissipate quickly. summer haze helps... you can actually see the wake
 
On my first solo, very first landing, I was extended on downwind to follow a 727 and cautioned for wake turbulence. I was in a Cessna 152. All was fine, but definitely focused my mind when I was already quite focused. 27 years ago.

Sorry for necro.
 
There are two kinds of unrelated wake turbulence.

Wingtip vortexes, as being discussed here in the regulations.

Traditional turbulence from the engines, left in the acceleration zone. This was well known for years, but not as violent as modern vortex turbulence, and tends to be forgotten.

The immense blast of thrust gasses behind a departing fully loaded jet take a while to dissipate, and although relatively harmless to very heavy airliners, can produce low altitude rolls and pitch motions that have caused crashes in the general aviation population. This was more evident in the trijet period, as the higher engine placement reduced friction with the ground, which tends to break up the turbulence.

Low to the runway engines do dissipate faster, but those are now much more powerful engines, so the problem remains.

Light planes aiming to touch down near the numbers to remain as far as possible from the point of rotation find themselves at very low altitude and speed as they enter this rolling air, and I have experienced airspeed oscillations of 10 to 20 knots, combined with rolls of 10 or more degrees behind a trijet.

I believe the controllers had this in mind when advising wake turbulence for your landing runway. This tends to take place within 50 feet or less altitude, a bad place to be dealing with such control requirements. Landing at BWI, JAX, STL, and SAV in a Cessna 172 educated me on this type of "wake turbulence".
 
Land shorter than the jet breaks ground. All you have is old jet blast. Taking off behind a jet is a different story.
 
Ed Haywood said:
On my first solo, very first landing, I was extended on downwind to follow a 727 and cautioned for wake turbulence. I was in a Cessna 152. All was fine, but definitely focused my mind when I was already quite focused. 27 years ago.

Sorry for necro.
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That ain’t no necro; Sour milk maybe, but no necro.
 
I get that all the time at KTOL. Even when its a small jet they will give me that warning. They have a small group of F16 at Toledo, and they will give you a caution if they are taking off in front of you. I'm not sure how much wake turbulence an F16 puts out but we all know what happened to Goose and Maverick!
 
Well technically the F-16 is a large (MTGW > 41,000) for ATC separation purposes. They have to issue the wake turbulence call for a small landing behind them departing/ arriving.

Back in the 90s, there was a UC-35 that got flipped on it back following a flight of 2 F-16s. I believe they were 3 miles in trail too.
 
When I was at Balad Air Base in Iraq, used to get an F16 airshow every hour or two, round the clock. Because of the ground fire threat, they always did max performance takeoffs. In an F16, that was roll with afterburners, fly at 10 feet AGL for full length of runway, then pull straight vertical and disappear from sight. That would probably make some fun wake turbulence for the Predators also taking off and landing.
 
WannFly said:
last evening, i was on a long straight in for rny 36, got a caution wake turbulence while i was 8 miles out for a departing big iron from rny 36. got me a little off-guard as to why do i care about his wake since i wasnt going through his flightpath, unless i am going around. got one more about 3 mile final as another big iron fedex took off.

I have always gotten the warning if i am taking off right after a big (very rare occurrence for me since i just proactively wait, or roll way past their take off point before my take off) one or even in the air if i am climbing and they are descending but this is the first time i have been issued that warning not once but twice while i am landing and they are taking off.

if it matters winds were 040 @5 on the surface, about 060@15 where i was on the glide path and rny 36 was being used.

thoughts?
Click to expand...

Say "Thank you" and put your mind to work on more important things.

Bob
 
Ed Haywood said:
When I was at Balad Air Base in Iraq, used to get an F16 airshow every hour or two, round the clock. Because of the ground fire threat, they always did max performance takeoffs. In an F16, that was roll with afterburners, fly at 10 feet AGL for full length of runway, then pull straight vertical and disappear from sight. That would probably make some fun wake turbulence for the Predators also taking off and landing.
Click to expand...

!!!!! uh, disregard. Roll as in take off roll
 
This is a few months old but it wasn’t mentioned- My father was Oakland center and trained controllers for a time- the light quartering wind is one of those specific situations that they are trained to give more robust wake turbulence warnings iaw- “if in your opinion”
Makes sense since we know vortices descend outward from the wingtip. The quartering light wind means they can be pushed over the runway and linger for a while. If you got light thermals that’ll help them linger without breaking them up as well. Controllers protect the arrival and the go around. You’re in control, but there should never be a situation where you don’t know about a hazard in a go around.
 

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